Best 273 and 318 builds (NO 360's please)

bkd said
This might be a stupid question, but here it goes, been following this thread and something just doesn't seem rite to me and that is this. I have a 318 my brother-inlaw had in an Ply-Arrow he built back in the 80's back then he bought a set of 340 heads with a tri-angle valve job done on them and found that it didn't help at all actually hurt the engine, and have been told this ever since I got the motor, no it not in my car yet I can only wish for that rite now. So how can you guy's be talking about putting 360 heads on a 318 when 340 heads aren't a good idea, is it because you guy's have the head cut down? per say. I don't understand and my head hurts and feels like it's going to explode LOL.
Brad

Air flow is what makes big power. Compression adds, but on a smaller scale. The combination of everything together makes it all work best. That is why a lot of these guys want more information, to give a good recommendation. If you put stock 360 or 340 heads on a 318 with stock 318 heads, it will make more power, assuming good cam, valve springs, intake and carb. The extra flow will more than make up for the lack of compression. If you port heads, 318, 340 or 360 then you are getting more flow. If you go to Magnum heads you add a little compression and more flow. Porting 318 heads can get more flow than stock 340 heads. Not all machine work is the same either. If you sink the valves they lose power. If you narrow the seats they don't last as long. I look at how much money I have and other factors, (complication, dependability, cross country driving, octane available, and anything else you want to add in) and start making decisions. This is of course, a very simplified explanation. What can you get and for how much does it cost? What is the gain? Its your time and money.